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-rw-r--r--lib/iov_iter.c75
1 files changed, 38 insertions, 37 deletions
diff --git a/lib/iov_iter.c b/lib/iov_iter.c
index c78129e709f2..a9446efac70d 100644
--- a/lib/iov_iter.c
+++ b/lib/iov_iter.c
@@ -1289,60 +1289,61 @@ static struct page **get_pages_array(size_t n)
return kvmalloc_array(n, sizeof(struct page *), GFP_KERNEL);
}
-static inline ssize_t __pipe_get_pages(struct iov_iter *i,
- size_t maxsize,
- struct page **pages,
- size_t off)
-{
- struct pipe_inode_info *pipe = i->pipe;
- ssize_t left = maxsize;
-
- if (off) {
- struct pipe_buffer *buf = pipe_buf(pipe, pipe->head - 1);
-
- get_page(*pages++ = buf->page);
- left -= PAGE_SIZE - off;
- if (left <= 0) {
- buf->len += maxsize;
- return maxsize;
- }
- buf->len = PAGE_SIZE;
- }
- while (!pipe_full(pipe->head, pipe->tail, pipe->max_usage)) {
- struct page *page = push_anon(pipe,
- min_t(ssize_t, left, PAGE_SIZE));
- if (!page)
- break;
- get_page(*pages++ = page);
- left -= PAGE_SIZE;
- if (left <= 0)
- return maxsize;
- }
- return maxsize - left ? : -EFAULT;
-}
-
static ssize_t pipe_get_pages(struct iov_iter *i,
struct page ***pages, size_t maxsize, unsigned maxpages,
size_t *start)
{
+ struct pipe_inode_info *pipe = i->pipe;
unsigned int npages, off;
struct page **p;
- size_t capacity;
+ ssize_t left;
+ int count;
if (!sanity(i))
return -EFAULT;
*start = off = pipe_npages(i, &npages);
- capacity = min(npages, maxpages) * PAGE_SIZE - off;
- maxsize = min(maxsize, capacity);
+ count = DIV_ROUND_UP(maxsize + off, PAGE_SIZE);
+ if (count > npages)
+ count = npages;
+ if (count > maxpages)
+ count = maxpages;
p = *pages;
if (!p) {
- *pages = p = get_pages_array(DIV_ROUND_UP(maxsize + off, PAGE_SIZE));
+ *pages = p = get_pages_array(count);
if (!p)
return -ENOMEM;
}
- return __pipe_get_pages(i, maxsize, p, off);
+ left = maxsize;
+ npages = 0;
+ if (off) {
+ struct pipe_buffer *buf = pipe_buf(pipe, pipe->head - 1);
+
+ get_page(*p++ = buf->page);
+ left -= PAGE_SIZE - off;
+ if (left <= 0) {
+ buf->len += maxsize;
+ return maxsize;
+ }
+ buf->len = PAGE_SIZE;
+ npages = 1;
+ }
+ for ( ; npages < count; npages++) {
+ struct page *page;
+ unsigned int size = min_t(ssize_t, left, PAGE_SIZE);
+
+ if (pipe_full(pipe->head, pipe->tail, pipe->max_usage))
+ break;
+ page = push_anon(pipe, size);
+ if (!page)
+ break;
+ get_page(*p++ = page);
+ left -= size;
+ }
+ if (!npages)
+ return -EFAULT;
+ return maxsize - left;
}
static ssize_t iter_xarray_populate_pages(struct page **pages, struct xarray *xa,